Developmental Language Disorder (DLD), formerly known as Specific Language Impairment (SLI), is a severe disorder with a prevalence of approximately 7% in the child population, that impact on oral and written communication, however, it is little known by clinicians and teachers, which prevents it from being detected and pedagogical responses given at the beginning of schooling. For this reason, we sought to describe and compare the knowledge of Primary School teachers about SLI/DLD in five aspects: definition, characteristics, causes, intervention and epidemiology. To this end, 107 teachers in Lima and Madrid completed a Sociodemographic Data Sheet and the Specific Language Impairment Knowledge Questionnaire. The results show statistically significant differences between the groups, with Spanish teachers performing better in the aspects of definition, characteristics, causes and epidemio...